Understanding of image making in the PNG-8 format with the PNG-24 format and the difference between

PNG, lossless compression is a bitmap graphics file formats. PNG format for non-distortion, compression, and allows the use of technology similar to a palette of GIF format, support true color images, and have the alpha channel (transparent), and other features. There are a lot of people use the PNG format and other aspects of the Internet.
PNG, lossless compression is a bitmap graphics file formats. PNG format for non-distortion, compression, and allows the use of technology similar to a palette of GIF format, support true color images, and have the alpha channel (transparent), and other features. There are a lot of people use the PNG format and other aspects of the Internet.

PNG of the English name for the Portable Network Graphics, is a portable network graphic. Another argument is that the name comes from the unofficial


features


* 256-color palette of techniques to produce small size files
* up to 48-bit true color images and 16-bit grayscale image.
* Alpha channel support, translucent properties.
* Support image brightness of the gamma correction information.
* Support to store additional text information in order to retain the image name, author, copyright, creation time, notes and other information.
* use lossless compression
* asymptotic display and streaming read and write, for fast transmission in the network and then displays the preview show the whole picture.
* CRC cyclic redundancy code to prevent the use of file error.
* new PNG standard allows multiple images stored in a file.


PNG is divided into two formats: PNG-8, and PNG-24. As with the GIF PNG-8 supports up to 256 colors, PNG-24 supports 48-bit true color, and sometimes better than the JPG, which is not in the scope.


how to generate PNG-8, and PNG-24 image? Use PS's If you use fireworks is the


one, PNG-8 and GIF


PNG-8 with the support of color as a transparent GIF. PNG-8 bit GIF has some, GIF PNG-8 there is not, for example: the same file format, PNG-8 is smaller than GIF.


Second, PNG-8 with the PNG-24 对 degree of support for IE6

PNG-24 supports alpha channel transparency formats, support for semi-transparent, IE6 does not support PNG-24, but he fully supports the PNG-8.
If it is opaque PNG-24, IE6 is the perfect support for the reason that IE6 does not support PNG-24 is because the PNG-24 in the semi-transparent will not display correctly in IE6.

III, PNG-8 transparent PNG-24 with the difference


PNG-8 and gif there are some similarities, are indexed color mode, only support pixel-level pure and transparent, does not support alpha transparency. We usually say But IE6 supports PNG-8 transparent, transparent gif the same as support.

four, PNG-8's high compression ratio


cutting diagram, sometimes choose PNG-8 can get a higher compression ratio. Note that PNG-8, not a PNG-24. But in some cases or gif or jpg will be smaller, according to the actual situation in order to choose the best option debug.